Functional Correlates of childhood maltreatment and symptom severity during affective theory of mind tasks in chronic depression

Abstract

Among multiple etiological factors of depressive disorders, childhood maltreatment (CM) gains increasing attention as it confers susceptibility for depression and predisposes to chronicity. CM assumedly inhibits social-cognitive development, entailing interactional problems as observed in chronic depression (CD), especially in affective theory of mind (ToM). However, the extent of CM among CD patients varies notably as does the severity of depressive symptoms. We tested whether the extent of CM or depressive symptoms correlates with affective ToM functions in CD patients. Regional brain activation measured by functional magnetic resonance imaging during an affective ToM task was tested for correlation with CM, assessed by the Childhood Trauma Questionnaire (CTQ), and symptom severity, assessed by the Montgomery-Åsberg Depression Rating Scale (MADRS), in 25 unmedicated CD patients (mean age 41.52, SD 11.13). Amygdala activation during affective ToM correlated positively with CTQ total scores, while (para)hippocampal response correlated negatively with MADRS scores. Our findings suggest that differential amygdala activation in affective ToM in CD is substantially modulated by previous CM and not by the pathophysiological equivalents of current depressive symptoms. This illustrates the amygdala's role in the mediation of CM effects. The negative correlation of differential (para)hippocampal activation and depressive symptom severity indicates reduced integration of interactional experiences during depressive states.

Keywords: Amygdala; Early trauma; Hippocampus; Mentalizing; Persistent depressive disorder; Social cognition; fMRI.